With reference to the technical bulletin in question, this has been produced to fully address this specific concern. While we can never fully guarantee that a concern will not recur in the future, any technical bulletin we release is done so to ensure a robust fix is implemented. We are confident that this will resolve any concerns that may be experienced of this nature moving forward.

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The kit in question includes the relevant latest parts and please be advised that during the course of manufacture of any of our components we will continually modify and improve the design where necessary.

In the past, superchargers have been known to produce noise. One source of noise stems from the pressure pulsations that occur as the lobes of the pump mesh and un-mesh during boosted operation. Another source of noise occurs during un-boosted operation, e.g. when the car is stopped and the engine is idling. In this case, vibrations produced by the normal combustion of the engine can be transferred through the belt and cause gear rattle in the supercharger. In a race setting, these various noises are at most a nuisance, but in passenger cars they can be perceived as a lack of quality or perhaps even a more significant problem with the engine itself.

One approach that Eaton uses to isolate the supercharger gears from the engine vibrations is a noise isolating coupling. A crucial component in this coupling is its Single Spring Isolator (SSI) which is situated between an inner and outer hub which enclose the spring in an internal cavity. Each hub is pressed onto its own mating shaft, with the input shaft connected to the front hub and with the rear hub pressed onto the shaft that drives the gears which compress and drive boosted air into the engine.